Description

Isaac Perea-Gil1,2, Maricela Prado1,2, Arne Bruyneel2, Wesley McKeithan2,3, Dries Feyen2,3, Pooja Nair1,2, Mark Mercola2,3 and Ioannis Karakikes1,2

1Department of Cardiothoracic Surgery; 2Stanford Cardiovascular Institute; 3Department of Medicine, Division of Cardiovascular Medicine, Stanford Medicine

Introduction: Familial dilated cardiomyopathy (DCM) is a leading cause of heart failure. To date, there is still a large gap in our understanding of the molecular events and signaling pathways that lead from a mutation to diverse disease phenotypes, and disease-modifying therapies are lacking. The development of induced pluripotent stem cell (iPSC) technology has enabled new opportunities to identify disease-modulating therapeutics and empowers comparatively rapid drug screening for human genetic diseases such as DCM.

Methods: iPSCs were generated from three DCM patients harboring a pathogenic mutation in the TNNT2 gene (p. Arg173Trp; TNNT2R173W) and differentiated towards cardiomyocytes (iPSC-CMs). We performed a primary phenotypic screening using high-throughput contractility assays in iPSC-CMs monolayers, and further validated our finding at the single cell and 3D engineered heart tissue levels.

Results: We tested a small molecule library of 200 well-characterized protein kinase inhibitors and identified two compounds that rescued the contractile deficit of TNNT2R173W iPSC-CMs. We pursued

two hits for further studies and demonstrated that these two kinase inhibitors when combined provided a synergistic effect.

Conclusions: Here we determined the feasibility of performing a primary phenotypic screen in DCM iPSC-CMs and demonstrated that small-molecule discovery using an iPSC-based disease model can identify candidate drugs for potential therapeutic intervention. The identification of compounds that increase contractility in DCM iPSC-CMs could yield novel therapies for genetic DCM.